With bug #110448 (Remove "Memory" page from Options dialog) fixed the corresponding help page needs to be changed:
As the options are still there, we could turn this into a guide page about modifying these settings (especially with the Quickstarter looking the most "useful"/user visible among them) using the Expert Configuration window.
Olivier Hallot committed a patch related to this issue.
It has been pushed to "master":
tdf#111083 Memory settings help page is gone too